1. Fields of the Invention
The present invention relates to a method for manufacturing a micro-miniature accelerometer which uses a cantilevered beam formed on a semiconductor substrate.
2. Prior Art
Recently, there has been developed a micro-miniature accelerometer which is formed on a semiconductor substrate.
Such a semiconductor accelerometer is formed on a semiconductor substrate using thin film technology such as etching. It is designed to detect the acceleration by sensing a resistance change due to the piezoresistance effect of a semiconductor or a minute capacity change due to deflection of a cantilevered beam.
Since such a semiconductor accelerometer is formed using thin film technology, as mentioned above, it has the excellent feature that it can be formed extremely small in size, for instance, with a length on the order on the 100 .mu.m, a thickness of order of 1 .mu.m, of the vibrating portion, and an overall chip size on the order on the 1 mm square, and in addition, that it can be formed on the same substrate for integrated circuit with other elements.
One such semiconductor accelerometer is described, for instance in "A Batch-Fabricated Silicon Accelerometer, IEEE Electron Devices", Vol. ED-26, No. 12, Dec. 1979, p. 1911.
The described conventional fabricating method is inconvenience to manufacturing accelerometers with high precision because the thickness of the cantilevered beams is controlled by regulating the temperature and the duration for etching.